Fugitive coloration



FUGITIVE COLORATION .lohn E. Livak, Clemson, S.C., asslgnor to DeeringMilliken Research Corporation, Pendleton, S.C., a corporation ofDelaware No Drawing. Application November 3, 1955 Serial No. 544,835

7 Claims. (Cl. 106-305) This invention relates to compositions for thefugitive tinting of organic non-cellulosic textile materials and is acontinuation in part of U8. application, Serial Number 203,215, filedDecember 28, 1950, now abandoned.

The fugitive tinting of organic non-cellulosic textile materialspresents special problems and this is particularly true of materialscontaining certain synthetic fibers. For example, nylon yarns aregenerally subjected to a heatsetting operation to set the twist thereinand if the nylon is tinted prior to this operation, the color becomesmore or less permanently fixed and is not removed by subsequentfinishing operations. Special reducing or oxidizing treatments are thennecessary to remove the tint from the nylon fibers. Even tints which arecompletely fugitive to nylon, when the tinted material is not subjectedto high temperatures, become permanent when the nylon is heat-set sothat dyes or the like suitable for the tinting of nylon materials arelimited in number.

It has previously been suggested that the ultramarine pigments might besatisfactorily employed Without permanent discoloration on nylon fabricswhich are subjected to heat-setting, but the use of such pigmentspresents a special problem, since the ultramarines are substantiallywater insoluble and cannot be used in solution form. It is,.therefore,necessary that an aqueous dispersion of the ultramarine pigment beemployed.

Prior the present invention, it has been impossible to prepare adispersion of an ultramarine pigment having suflicient stability to besatisfactorily employed as a fugi-- tive tint in a conventional mannerand this has severely limited the use of such pigments. It isconventional to prepare sufiicient tinting solution or the like to lastfor a period of several days and to withdraw smaller quantities of thetint as needed. The use of an unstable dispersion requires that freshdispersions be prepared several times a day or else it requires thatfacilities for re'dispersing the pigment immediately prior to its use bereadily available. Further, it is generally necessary that the smallerquantity of the unstable pigment dispersion contained in the tintapplicator be agitated in order to obtain an even application, so thatit can be seen that the use of an unstable pigment dispersion as afugitive tint has several severe disadvantages.

It is an object of this invention to provide aqueous dispersions ofultramarine pigments which are stable for long periods of time and whichare suitable for the fugitive tinting of organic non-cellulosic textilematerials.

According to this invention there is provided an aqueous dispersion ofan ultramarine pigment comprising from about 25% to 75 by weight of theultramarine pigment, of a water solublesalt selected from the groupconsisting of sodium sulfate, sodium silicate, sodium sulfite and sodiumformate, and from about 50% to 200%, by weight of the ultramarinepigment, of a fatty acid-sodium soap. That the use of an inorganic saltwith a sodium soap could result in a stable emulsion is indeedsurprising in view of the known fact that inorganic salts generally actto break emulsions or dispersions and are conven- United States Patentfect.

. weight of pigment.

2,920,975 Patented Jan. 12, 1960 "ice,

known or understood, but the stabilizing influence is I presentlybelieved to be the result of a common ion ef- This, however, is onlytheory and applicants do not wish to be limited thereby.

Any of the well known ultramarine pigments can suitably be employed inthe preparation of the new dispersions of this invention, and typicalexamples of suitable pigments include ultramarine blue, ultramarine red,ultramarine green and ultramarine violet. These pigments are in eachinstance commercially available materials. The amount of the inorganicpigment to be employed depends primarily on the depth of shade desiredand solutions having a concentration of ultramarine pigment of fromabout 1% to 20% by weight can satisfactorily be prepared. Generally,however, the most stable dispersions result when the concentration ofultramarine pigment is from about 2% to 10% by weight.

The amount of inorganic salt to be employed in the pre paration of thenew compositions of this invention can be varied within reasonably widelimits although if too little or too much of the inorganic salt isemployed, the stability of the emulsion is not as great as might bedesired. As a general rule a reasonably stable emulsion can be preparedusing from about 25 to by weight of the ultramarine pigment, of theinorganic salt but best results are generally obtained when the weightof the inorganic salt is from about 30% to 60% of the Any of theinorganic salts listed above can satisfactorily be employed but sodiumsulfate is generally preferred.

Any of the well known and commercially available fatty acid sodium soapscan suitably be employed in forming the new dispersions and specificillustrative examples of suitable soaps include sodium palmitate, sodiumoleate, sodium stearate or mixtures of the same. Sodium oleate isgenerally preferred for reasons of convenience. The amount of soap to beemployed can be varied within reasonably wide limits and a weight ofsoap equal to from about 50% to 200% of the weight of ultramarinepigment will generally give satisfactory results. For the greatestdegree of stability, however, the soap is preferably employed in amountsof from about 75% to by weight of the ultramarine pigment.

The new dispersions of this invention can be employed for the fugitivetinting of any organic non-cellulosic textile material as illustrated bywool, nylon, polyacrylonitrile fibers such as sold under the trade namesof Orlon and Acrilan, polyester fibers such as those prepared fromterephthalic acid and ethylene glycol and sold under the name of Dacronand mixtures of such materials. The new dispersions are particularlyadvantageous for use on the synthetic hydrophobic fibers and, aspreviously mentioned, even when such materials are subjected to steamingat high temperatures, the tint can be removed therefrom by a simplescouring operation. Ultramarine blue is an especially valuable tintingmaterial in this respect since the color is completely destroyed in acidmedia and a slightly acid scour can be employed to remove even the lasttraces of residual color.

The tinting dispersion can be applied in any suitable or conventionalmanner. For example, the dispersion can be sprayed on loose staplefibers, applied by brushing to either fibers or yarn, or can be appliedby passing yarn over a wick applicator. If desired, the dispersions canbe diluted, at the time of use, to any suitable concentration withoutdestroying the stability of the dispersions to the extent that theybreak while being applied and, if desired, conventional penetrants,lubricants and sizes can also be included in the tinting dispersion.

When ultramarine blue is employed as a tint on Wool I or blends of woolwith non-cellulosic fibers, it is necessary to keep the tinting solutionon the alkaline side. This is because wool is acidic in nature and whena neutral tinting dispersion containing ultramarine blue is sprayed onthe wool, the acidic nature of the wool slowly effects decolorization ofthe pigment. A satisfactory procedure comprises adding to the tintingdispersion a mild alkali, such as sodium carbonate, in sufiicientquantities to overcome the acidity of the wool, so that the colorremains visible until it is removed by scouring. This procedure isnecessary, however, only when employing ultramarine blue on wool or woolblends and when other ultramarine pigments are employed, or whenultramarine blue is employed only on synthetic fibers, neutral tintingsolutions are quite satisfactory.

The invention will now be illustrated by the following specific examplesin which all parts are by weight unless otherwise indicated.

Example I In 50 parts by weight of water there is dissolved '5 parts byweight of sodium sulfate and to the resulting solution there is added 10parts of a finely pulverized ultramarine blue pigment. There is thenadded 200 parts of a 5% by weight solution of sodium oleate and theresulting mixture is agitated sufficiently to obtain complete dispersionof the pigment. This mixture is suitable for use Without dilution as afugitive tint or if desired can be diluted to any desired concentrationat the time of application. It is stable for at least a period of weeksand in an actual test on a dispersion prepared in the manner described,no visible break was apparent in a quantity of the dispersion which wasallowed to sit for a period of three weeks without agitation.

; With satisfactory results, one can substitute an equivalent quantityof ultramarine red or ultramarine green for the ultramarine blueemployed above. Likewise, one can substitute an equivalent quantity ofsodium silicate, or other inorganic salt of the class previouslydefined, for the sodium sulfate employed above, or one can substitute anequivalent quantity of sodium stearate, or other sodium soap, for thesodium oleate employed in the above example.

Example II To show the stabilizing influence of an inorganic salt suchas employed in the first example, parts by weight of the ultramarineblue pigment employed in Example I are added to 50 parts by weight ofwater and to the resulting mixture there is added 200 parts of a 5% byweight sodium oleate solution. The resulting mixture is agitated, as inthe first example, to result in the ultramarine pigment being completelydispersed, and the result ing dispersion is thereafter allowed to standat room temperature without agitation. In an actual test, a dispersionprepared according to this procedure displayed a noticeable break afteronly about 5 minutes and was completely stratified in less than onehour. Inasmuch as the dispersion of this example was prepared in amanner identical to that of the previous example except for the omissionof the inorganic salt, the stabilizing effect of the salt is quiteapparent.

Example III The solution of Example I is diluted 300% with tap water andapplied by spraying to 100% nylon staple. The staple is stained adistinguishing blue color. The staple is thereafter formed into a nylontaffeta fabric and is finished in a conventional manner which includesscouring in soap and water. The finished fabric is examined and found tobe completely devoid of residual tint.

Having thus described my invention, what I desire to claim and secure byLetters Patent is:

1. As a new composition, an aqueous dispersion of an ultramarine pigmentcomprising from about 25% to 75%, by weight of the ultramarine pigment,of a water soluble salt selected from the group consisting of sodiumsulfate, sodium silicate, sodium sulfite and sodium formate, and fromabout to 200%, by weight of the ultramarine pigment, of a fattyacid-sodium soap.

2. A composition as in claim 1 wherein the inorganic salt is sodiumsulfate.

3. A composition as in claim 2 wherein the sodium soap is sodium oleate.

4. A composition as in claim 1 wherein the ultramarine pigment is anultramarine blue pigment.

5. As a new composition, a 2% to 10% by weight aqueous dispersion of anultramarine pigment containing between about 30% to by weight of theultramarine pigment, of a water soluble salt selected from the groupconsisting of sodium sulfate, sodium silicate, sodium sulfite and sodiumformate, and from about to by weight of the ultramarine pigment, of afatty acidsodium soap.

6. A composition as in claim 5 wherein the inorganic salt is sodiumsulfate and the sodium soap is sodium oleate.

7. A composition as in claim 6 wherein the ultramarine pigment is anultramarine blue pigment.

References Cited in the file of this patent UNITED STATES PATENTS2,207,696 Robinson July 9, 1940 2,564,225 Mayers Aug. 14, 1951 2,623,834Armitage Dec. 30, 1952 OTHER REFERENCES Colour Index, by F.- M. Rowe,pub. by the Society at the General Office, Bradford, Yorkshire, England,page 310.

1. AS A NEW COMPOSITION, AN AQUEOUS DISPERSION OF AN ULTRAMARINE PIGMENTCOMPRISING FROM ABOUT 25% TO 75%, BY WEIGHT OF THE ULTRAMARINE PIGMENT,OF A WATER SOLUBLE SALT SELECTED FROM THE GROUP CONSISTING OF SODIUMSULFATE, SODIUM SILICATE, SODIUM SULFITE AND SODIUM FORMATE, AND FROMABOUT 50% TO 200%, BY WEIGHT OF THE ULTRAMARINE PIGMENT, OF A FATTYACID-SODIUM SOAP.